PS2 (Ext)-6
Students demonstrate an understanding of physical, chemical, and nuclear changes by... 6aa-using chemical equations and information about molar masses to predict quantitatively the masses of reactants and products in chemical reactions.
National Standards:
Context of Lesson:
This laboratory exercise is designed to assess students' ability to practically apply what they have learned to a real situation. It will be split up into two parts to be incorporated into the lesson sequence where indicated. Part I will deal mainly with the concept of mole-mass relationships, and Part II will demonstrate percent composition. Part I should take anywhere from 30-40 minutes, and Part II should take 20-30 minutes. Where are these parts placed in the other lesson plans? I am confused.
Opportunities to Learn:
Depth of Knowledge
You should describe the DOKs
Prerequisite Knowledge
Students should know how to:
Calculate the number of moles in a given mass of an element
Calculate the mass and the number of moles given a percent composition
Plans for Differentiating Instruction
At risk students should be paired up with students who have a good handle on the material. This tactic will require close observation due to the fact that it will be very easy for the at risk student to simply copy from the higher level student.
Accommodations and modifications
Environmental factors
Their is a smartboard in the front of the room which will be used to demonstrate calculations (if needed). Desk are set-up in rows. There are six lab benches located along the walls in the classroom which can be used to set up the balance stations so that students are able to mass out their pennies.
Materials
1 bag of 5 pennies (ranging in years from 1960 - present) per student
At least 2 electronic balances
Students will need their calculators, pens/pencils, and textbooks
Periodic table
Objectives:
Students will convert from mass to number of moles (mole-mass relationships)
Students will calculate conversions from percent composition to mass and number of moles
To learn about the chronology of the metal composition of the cent coin (penny) and describe how it has changed
Instruction:
Opening:
Explain to students that this is a two part laboratory exercise in which we will learn about the composition of a penny. Advise students that they will not be dealing with any hazardous materials in either part of the exercise, but that they are still expected to follow laboratory safety procedures. Before they begin Part I briefly go over what they are expected to do. What is the question that they will be investigating?
Engagement:
Part I: Mole-Mass Relationships
For Part I explain to students that they will be given a plastic bag containing five pennies of varying years (each bag should contain pennies from both before 1982 and after 1982). Give them the following handout containing their data sheet and instructions:
After they have finished compiling their data go over any trends that they see. Ask them if they see an difference in the number of moles in pennies from different years. Explain to them that the numbers should be different and that you will explain why in Part II of the exercise - leave them hanging/wanting more.
Part II: Percent Composition
You should ask a question that is worth answering. Why should students care about the history of the penny. What they might be interested in is an anomaly in their data. Can you orchestrate the discussion so that they accept the anomaly, i.e. that there are two distinct populations of seemingly identical pennies?
For Part II begin by readdressing the fact that the number of moles in pennies from different years should be different. Now explain why by giving the students a brief chronology of the metal composition of the penny:
From 1793 to 1837 the composition was pure copper.
From 1837 to 1857, the cent was made of bronze (95% copper, and five percent tin and zinc).
From 1857 to 1863, the cent consisted of 88% copper and 12% nickel, which gave the coin a whitish appearance.
The cent was bronze again (95% copper, and five percent tin and zinc) from 1864 to 1962 with one exception. In 1943, the coin's composition was changed to zinc-coated steel. This change was only for the year 1943 and was due to the critical use of copper for the war effort (WWII). However, a limited number of copper pennies were minted that year. These are rare collectibles and are very valuable (refer to the similarities of the 1909 S VDB penny worth over $500.00). Show an example of this coin from the coin folder.
In 1962, the cent's tin content, which was quite small to begin with, was removed. That made the metal composition of the cent 95% copper and 5% zinc.
The alloy remained the same until 1982, when the composition was changed to 97.5% zinc and 2.5% copper (copper plated zinc). Cents of both compositions appeared in that year.
With this knowledge students will now be asked to take the percent composition (refer to chronology) of the pennies which they have already massed and calculate the the masses and number of moles of each element (copper and zinc) contained in each of their pennies. The data that they calculate will go into the following table on the data sheet for Part II:
If I was a students, I would not find this as interesting as using my penny data to try and determine these changes in composition.How would you recast this activity as an investigation?
Closure:
Students will be asked to hang onto their data sheets from Part I until they begin Part II, as they will need their data from Part I to complete Part II. When the data sheet from Part II is complete both data sheets will be handed in as a single assignment. There will be ample time for questions about penny composition and facts at the end of Part II. Be sure to explain to students that the examples gone over in class pertaining to percent composition were dealing mainly with compounds. Impress upon them that copper and zinc do not combine to form a chemical compound and therefore we cannot calculate an empirical or molecular formula (which we will learn about next class)
Will your students have to explain what they did and how their work serves as evidence for knowing the penny compositions?
Assessment:
Students will be assessed via the artifact that they turn in (data sheets from Parts I and II). They will be graded on accurate organized data and the use of the correct composition to come up with the most accurate data for Part II.
Lesson Plan
Lesson Title: Making Cents of Penny Composition
State Standards: GLEs/GSEs
PS2 (Ext)-6Students demonstrate an understanding of physical, chemical, and nuclear changes by...
6aa-using chemical equations and information about molar masses to predict quantitatively the masses of reactants and products in chemical reactions.
National Standards:
Context of Lesson:
This laboratory exercise is designed to assess students' ability to practically apply what they have learned to a real situation. It will be split up into two parts to be incorporated into the lesson sequence where indicated. Part I will deal mainly with the concept of mole-mass relationships, and Part II will demonstrate percent composition. Part I should take anywhere from 30-40 minutes, and Part II should take 20-30 minutes. Where are these parts placed in the other lesson plans? I am confused.Opportunities to Learn:
Depth of Knowledge
You should describe the DOKsPrerequisite Knowledge
Students should know how to:Plans for Differentiating Instruction
At risk students should be paired up with students who have a good handle on the material. This tactic will require close observation due to the fact that it will be very easy for the at risk student to simply copy from the higher level student.Accommodations and modifications
Environmental factors
Their is a smartboard in the front of the room which will be used to demonstrate calculations (if needed). Desk are set-up in rows. There are six lab benches located along the walls in the classroom which can be used to set up the balance stations so that students are able to mass out their pennies.Materials
Objectives:
Instruction:
Opening:
Explain to students that this is a two part laboratory exercise in which we will learn about the composition of a penny. Advise students that they will not be dealing with any hazardous materials in either part of the exercise, but that they are still expected to follow laboratory safety procedures. Before they begin Part I briefly go over what they are expected to do. What is the question that they will be investigating?Engagement:
Part I: Mole-Mass RelationshipsFor Part I explain to students that they will be given a plastic bag containing five pennies of varying years (each bag should contain pennies from both before 1982 and after 1982). Give them the following handout containing their data sheet and instructions:
After they have finished compiling their data go over any trends that they see. Ask them if they see an difference in the number of moles in pennies from different years. Explain to them that the numbers should be different and that you will explain why in Part II of the exercise - leave them hanging/wanting more.
Part II: Percent Composition
You should ask a question that is worth answering. Why should students care about the history of the penny. What they might be interested in is an anomaly in their data. Can you orchestrate the discussion so that they accept the anomaly, i.e. that there are two distinct populations of seemingly identical pennies?
For Part II begin by readdressing the fact that the number of moles in pennies from different years should be different. Now explain why by giving the students a brief chronology of the metal composition of the penny:
- From 1793 to 1837 the composition was pure copper.
- From 1837 to 1857, the cent was made of bronze (95% copper, and five percent tin and zinc).
- From 1857 to 1863, the cent consisted of 88% copper and 12% nickel, which gave the coin a whitish appearance.
- The cent was bronze again (95% copper, and five percent tin and zinc) from 1864 to 1962 with one exception. In 1943, the coin's composition was changed to zinc-coated steel. This change was only for the year 1943 and was due to the critical use of copper for the war effort (WWII). However, a limited number of copper pennies were minted that year. These are rare collectibles and are very valuable (refer to the similarities of the 1909 S VDB penny worth over $500.00). Show an example of this coin from the coin folder.
- In 1962, the cent's tin content, which was quite small to begin with, was removed. That made the metal composition of the cent 95% copper and 5% zinc.
- The alloy remained the same until 1982, when the composition was changed to 97.5% zinc and 2.5% copper (copper plated zinc). Cents of both compositions appeared in that year.
With this knowledge students will now be asked to take the percent composition (refer to chronology) of the pennies which they have already massed and calculate the the masses and number of moles of each element (copper and zinc) contained in each of their pennies. The data that they calculate will go into the following table on the data sheet for Part II:If I was a students, I would not find this as interesting as using my penny data to try and determine these changes in composition. How would you recast this activity as an investigation?
Closure:
Students will be asked to hang onto their data sheets from Part I until they begin Part II, as they will need their data from Part I to complete Part II. When the data sheet from Part II is complete both data sheets will be handed in as a single assignment. There will be ample time for questions about penny composition and facts at the end of Part II. Be sure to explain to students that the examples gone over in class pertaining to percent composition were dealing mainly with compounds. Impress upon them that copper and zinc do not combine to form a chemical compound and therefore we cannot calculate an empirical or molecular formula (which we will learn about next class)Will your students have to explain what they did and how their work serves as evidence for knowing the penny compositions?
Assessment:
Students will be assessed via the artifact that they turn in (data sheets from Parts I and II). They will be graded on accurate organized data and the use of the correct composition to come up with the most accurate data for Part II.Reflections
(only done after lesson is enacted)Student Work Sample 1 – Approaching Proficiency:
Student Work Sample 2 – Proficient:
Student Work Sample 3 – Exceeds Proficiency: